On March 4, 2014, the USPTO issued a Guidance memorandum for examination of subject matter eligibility under 35 U.S.C. § 101 in view of AMP v. Myriad (2013) and Mayo v. Prometheus (2012). Under the new guidelines, the examiner will first determine whether the claim recites or involves one or more of laws of nature/natural principles, natural phenomena, and natural products, i.e., judicial exceptions. If it does not, the claim is patent eligible, provided it is directed to one of the four statutory patent-eligible subject matter categories. If it does, the examiner will weigh multiple factors to determine whether the claim as a whole recites something significantly different than the judicial exception(s) and thus is patent eligible.

The Guidance identifies the following factors weighing toward patent eligibility: a) Claim is a product claim reciting something that is non naturally occurring and markedly different in structure from naturally occurring products; Claim recites elements/steps b) that impose meaningful limits on claim scope, so that others are not substantially foreclosed from using the judicial exception(s); c) that relate to the judicial exception in a significant way; d) that do more than describe the judicial exception(s) with general instructions to apply or use the judicial exception(s); e) that include a particular machine or transformation of a particular article, where the particular machine/transformation implements one or more judicial exceptio (s) or integrates the judicial exception(s) into a particular practical application; f) that add a feature that is more than well-understood, purely conventional or routine in the relevant field.